The issue of plasma triglyceride levels relative to the risk of development of cardiovascular disease, as well as overall mortality, has been actively discussed for many years. Like other cardiovascular disease risk factors, final plasma TG values have environmental influences (primarily dietary habits, physical activity, and smoking), and a genetic predisposition. Rare mutations (mainly in the lipoprotein lipase and apolipoprotein C2) along with common polymorph isms (within apolipoprotein A5, glucokinase regulatory protein, apolipoprotein B, apolipo - protein E, cAMP responsive element binding protein 3 -like 3 , glycosylphosphatidylinositol- anchored HDL -binding protein 1) play an important role in determining plasma TG levels., L. Schwarzova, J. A. Hubacek, M. Vrablik., and Obsahuje bibliografii
Genetic strain-dependent reactivity to mechanical stimuli in rat skeletal muscle has not been examined. This study aimed to examine whether genetic strain-dependency is associated with reactivity in protein metabolism and the resultant muscle hypertrophy after isometric resistance training (RT). The right triceps of Sprague-Dawley (SD) and Wistar rats underwent 12 sessions of RT. After RT, a transition from the IIb to the IIx myosin heavy-chain isoform was observed in both strains. In SD rats, the lateral gastrocnemius muscle (LG) mass of the trained legs (TRN) was significantly higher than that of the control legs (CON) (7.8 %, P<0.05). Meanwhile, in Wistar rats, the LG mass was unchanged. In SD rats, the levels of 70-kDa ribosomal protein S6 kinase (p70S6k) and forkhead box 3a (FOXO3a) phosphorylation in the TRN were significantly greater than those of the CON (2.2- and 1.9-fold, respectively; P<0.05). The expression of muscle ring finger-1 (MuRF1) and muscle atrophy F-box (MAFbx/atrogin-1) in the TRN were significantly lower than those of the CON (0.6- and 0.7-fold, respectively; P<0.05). However, in Wistar rats, there was no significant difference. These results suggest a genetic strain difference in protein metabolism. This phenomenon may be useful for studying individual differences in response to RT., K. Kobayashi ... [et al.]., and Obsahuje seznam literatury
A common variant of the LHb subunit has a varying prevalence in various ethnic groups. The consequences of the presence of mutated luteinizing hormone (LH) concern borderline alterations in pituitary/gonadal function that could be mediated by an altered action of variant LH on gonadal steroidogenesis. A comparison of plasma concentrations of gonadal steroid sex hormones was completed in women heterozygous for variant LH and in women with the wild type of LH in three different age ranges. The sample was a randomly selected group of 177 normal women 16 to 72 years old. Variant LH was determined by immunofluorimetric methods using two combinations of monoclonal antibodies. The ratios of LH measured by the two assays indicated whether the subject was wild type homozygote, heterozygote or homozygote for the variant LHb allele. The carriers of the variant LH allele in the group of postmenopausal women showed higher serum testosterone levels than those with the wild type LH. This is in agreement with the clinical observations made previously showing a slightly higher androgenic action in the population with variant LH. No differences were detected in serum LH, FSH, epitestosterone and sex hormone binding globulin (SHBG)., M. Hill, I.T. Huhtaniemi, R. Hampl, L. Stárka., and Obsahuje bibliografii
Mutations in troponin T (TNNT2) gene represent the important part of currently identified disease-causing mutations in hypertrophic (HCM) and dilated (DCM) cardiomyopathy. The aim of this study was to analyze TNNT2 gene exons in patients with HCM and DCM diagnosis to improve diagnostic and genetic consultancy in affected families. All 15 exons and their flanking regions of the TNNT2 gene were analyzed by DNA sequence analysis in 174 patients with HCM and DCM diagnosis. We identified genetic variations in TNNT2 exon regions in 56 patients and genetic variations in TNNT2 intron regions in 164 patients. Two patients were found to carry unique mutations in the TNNT2 gene. Limited genetic screening analysis is not suitable for routine testing of disease-causing mutations in patients with HCM and DCM as only individual mutation-positive cases may be identified. Therefore, this approach cannot be recommended for daily clinical practice even though, due to financial constraints, it currently represents the only available strategy in a majority of cardio-centers., M. Jáchymová ... [et al.]., and Obsahuje seznam literatury
Metabolic disorders such as obesity, insulin resistance and other components of metabolic syndrome (MetS) are connected with birth weight. Low and high birth weight is associated with a higher risk of developing type 2 diabetes mellitus, the mechanism is not clear. In this study, we evaluated the association between birth weight and anthropometric as well as biochemical components of MetS in women with a history of gestational diabetes mellitus (GDM) in comparison with control women. In part of the GDM group, we re-evaluated metabolic changes over 5-8 years. Anthropometry, blood pressure, glucose metabolism during the 3-h oGTT, lipid profile, uric acid, thyroid hormones, and liver enzymes were assessed. From the analyzed components of MetS in adult women we proved the association of low birth weight (birth weight <25th percentile) with glucose processing, in particular among women with a history of GDM. Low birth weight GDM women revealed significantly higher postchallenge insulin secretion and lower peripheral insulin sensitivity. Re-examinations indicate this association persists long after delivery., D. Vejrazkova, P. Lukasova, M. Vankova, O. Bradnova, G. Vacinova, J. Vcelak, V. Cirmanova, K. Andelova, H. Krejci, B. Bendlova., and Obsahuje bibliografii
Ghrelin is a new endogenous peptide, discovered in 1999 by Kojima et al., as the result of a search for an endogenous ligand for an orphan receptor of known structure and function. Ghrelin is composed of 28 amino acids and is produced mostly by cells of the stomach, hypothalamus, and hypophysis, but it has also been detected in other tissues. Its discovery is related to the development of a new hypothesis regarding the regulation of growth hormone secretion. It is an antagonist of somatostatin. Ghrelin activates the release of growth hormone from the somatotrophic cells of the hypophysis. It participates in the regulation of energy homeostasis, increases food intake, decreases energy output and exerts a lipogenetic effect. Its metabolic effects do not depend on the GH/IGF-I system, but are mediated by the NPY/Y1 and AGRP receptor system. Ghrelin influences the secretion and motility of the gastrointestinal tract, especially the stomach. The presence of ghrelin and its receptors has also been demonstrated in many other tissues. Its function in these tissues has not yet been studied, thus providing many possibilities for further research., M. Rosická, M. Kršek, Z. Jarkovská, J. Marek, V. Schreiber., and Obsahuje bibliografii
Ghrelin and agonists of its re ceptor GHS-R1a are potential substances for the treatment of cachexia. In the present study, we investigated the acute and lo ng-term effects of the GHS-R1a agonist JMV 1843 (H-Aib-DTrp-D-gTrp -CHO) on food intake, body weight and metabolic parameters in lean C57BL/6 male mice. Additionally, we examined stability of JMV 1843 in mouse blood serum. A single subcutaneous injection of JMV 1843 (0.01-10 mg/kg) increased food intake in fed mice in a dose- dependent manner, up to 5-times relative to the saline-treated group (ED 50 =1.94 mg/kg at 250 min). JMV 1843 was stable in mouse serum in vitro for 24 h, but was mostly eliminated from mouse blood after 2 h in vivo . Ten days of treatment with JMV 1843 (subcutaneous administration, 10 or 20 mg/kg/day) significantly increased food intake, body weight and mRNA expression of the orexigenic neuropeptide Y and agouti-related peptide in the medial basal hy pothalamus and decreased the expression of uncoupling protein 1 in brown adipose tissue. Our data suggest that JMV 1843 could have possible future uses in the treatment of cachexia., M. Holubová, ... [et al.]., and Obsahuje seznam literatury
GIP (glucose dependent insulinotr ophic polypeptide), originally identified as an incretin peptide synthesized in the gut, has recently been identified, along with its receptors (GIPR), in the brain. Our objective was to investigate the role of GIP in hypothalamic gene expression of biomarkers linked to regulating energy balance and feeding behavi or related neurocircuitry. Rats with lateral cerebroventricular cannulas were administered 10 μg GIP or 10 μl artificial cerebrospinal fluid (aCSF) daily for 4 days, after which whole hypothalami were collected. Real time Taqman™ RT-PCR was used to quantitatively compare the mRNA expression levels of a set of genes in the hypothalamus. Administration of GIP resulted in up-regulation of hypothalamic mRNA levels of AVP (46.9±4.5 %), CART (25.9±2.7 %), CREB1 (38.5±4.5 %), GABRD (67.1±11 %), JAK2 (22.1±3.6 %), MAPK1 (33.8±7.8 %), NPY (25.3±5.3 %), OXT (49.1±5.1 %), STAT3 (21.6±3.8 %), and TH (33.9±8.5 %). In a second experiment the same set of genes was evaluated in GIPR -/- and GIPR +/? mice to determine the effect of lack of GIP stimulation on gene expression. In GIPR -/- mice expressions of the following genes were down-regulated: AVP (27. 1±7.5 %), CART (28.3±3.7 %), OXT (25.2±5.8 %), PTGES (23.9±4.5 %), and STAT3 (8.8±2.3 %). These results suggest that AVP, CART, OXT and STAT3 may be involved in energy balance-related hypothalamic circuits affected by GIP., S. Ambati ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
In order to elucidate the direct effect of glucose on lipolysis in isolated rat adipocytes, cells were incubated in a buffer with different concentrations of this sugar: 2, 8 or 16 mmol/l. The increase in glucose concentration from 2 mmol/l to 8 or 16 mmol/l enhanced basal lipolysis by 30% and 47 %, respectively. Epinephrine-induced lipolysis (1 m mol/l) was also increased by 31 % and 32 %, when glucose concentration was increased from 2 mmol/l to 8 or 16 mmol/l, respectively. The rise in lipolysis caused by glucose was restricted by H-89 (an inhibitor of protein kinase A, 30 µmol/l), but insulin (1 nmol/l) had no inhibitory action. The augmentation of lipolysis by glucose did not require its metabolism (as demonstrated using 2-deoxyglucose) and was due to the action of this sugar on the final steps of the lipolytic cascade, particularly on protein kinase A. However, short-term exposure of adipocytes to higher glucose concentrations did not restrict the inhibitory action of insulin on lipolysis induced by epinephrine., T. Szkudelski, K. Szkudelska., and Obsahuje bibliografii